These modeling results are supported by experimental studies that
have shown that copper in presence of DOM readily forms copperDOM
complexes (Römkens and Dolfing, 1998; Hsu and Lo, 2000; Yin
et al., 2002) and that DOM can enhance the mobility of copper
(Temminghoff et al., 1997). The presence of carboxyl groups identified
by the spectroscopic characterization of the leachate further supports
the formation of Cu-DOM complexes identified in the modeling